简介:这篇论文评估方法由Engelund和汉森,开发了的沉积运输的适用性Ackers和怀特,杨等,和货车Rijn和方法在中国开发了的武汉,到黄河,它高度专注并且有细密纹理的沉积。沉积数据从实验室斜槽从黄河,从一条运河的数据的32个集合,和数据的266个集合包括超过1000观察。最好的预言被吴并且长被Yang1996方法,武汉方法,和修改武汉方法获得,当相当好的预言被货车Rijn2004方法也提供时。Engelund和汉森,Ackers和怀特,和在他们的原来的形式的货车Rijn1984方法不对黄河适用。全部的负担集中的预言的结果像一样为床材料集中,尽管全部的负担包括大部分洗负担。
简介:Graphenenanostructures为未来nanoelectronics正在答应候选人并且固态量信息技术。在这评论,我们提供蚀刻的graphenenanostructures的很多个电子运输实验的概述。我们简短重游电子性质和体积的运输特征,即,二维的graphene。为使graphene成为象nanoribbons,单个电子晶体管和量点那样的nanostructures的制造技术,主要基于干燥蚀刻paper-cutting,技术详细被讨论。当我们构画出nanostructured设备的量运输性质时,当前的制造技术的限制被讨论。特别地,我们通过graphenenanoribbons和收缩这里集中于运输,象在包括的graphene量点上一样的单个电子晶体管加倍量点。这些quasi-one-dimensional(nanoribbons)和quasi-zero-dimensional(量点)graphenenanostructures表演怎么克服由侧面的graphene门和费用察觉者允许单个搬运人和他们的控制的监禁的graphene的无差距的性质的一条清楚的线路。特别地,我们强调那graphene量点,两倍量点是为基于纺纱的稳固的状态的很有希望的系统量计算,自从他们被相信有特别长,由于弱纺纱轨道在graphene联合和弱hyperfine相互作用旋转连贯时间。
简介:Thepaperprovidesacomprehensivetestingoftheapplicabilityof13sedimenttransportformulasunderdifferentflowandsedimentconditions.Thedimensionlessparametersusedfortestingthereliabilityandsensitivityofformulasaredimensionlessparticlediameter,relativedepth,Froudenumber,relativeshearvelocity,dimensionlessunitstreampower,andsedimentconcentration.Atotalof3,391setsoflaboratoryandriverdataareusedinthetests.Engineersmayfindthetestresultsusefultotheirselectionofformulasunderdifferentflowandsedimentconditions.
简介:Thispaperstudiestheflowstructureandthebedloadtransportregimeinbackwaterflows,toprovideatheoreticalsupportforsolvingthesedimenttransportandbedscourproblemsinriversorreservoirswithbackwater.Thebedloadtransportratesunderdifferentconditionsareanalyzedfirstonthebasisoftheoreticalanalysis,measurementcomparisonandflumeexperiment,anditispointedoutthattheexistingformulasforthebedloadtransportratearenotapplicableforthebedloadtransportrateinbackwaterflows.Next,theflowstructureinanon-uniformflowisobservedbyflumeexperiments,andbyintroducingthebackwaterdegreeindex,thequantitativerelationbetweentherelativebedshearstressandthebackwaterdegreeisobtained.Finally,theformulaforthebedloadtransportrateapplicableforthereservoirchannelsegmentwithbackwaterflowsisobtainedthroughmeasurementsandflumeexperiments.
简介:ThehydrodynamicandthesedimenttransportpatternswithintheestuaryoftheYangtzeRiverarecomplexbecauseofinteractionoffluvialandthetidalforces,dependingonfreshwaterdischargeandtidalrange.Basedonthedatameasuredinrecentyears,thispaperdiscussesthecharacteristicsofflowandsedimentmovementintheYangtzeRiverEstuaryandtheirinfluencesontheevolutionoftheestuary.
简介:Fromthegroupmovementofthebedloadwithinthebottomlayer,detailsofthenonlineardynamiccharacteristicsofbedloadmovementarediscussedinthispaper.Whetherthesedimentisinitiatedintomotioncorrespondstowhethertheconstanttermintheequationisequaltozero.Ifconstanttermiszeroandnodispersiveforceisconsidered,theequationrepresentsthetraditionalShieldsinitiationcurve,andifconstanttermiszerowithoutthedispersiveforcebeingconsidered,thenanewShieldscurvewhichismuchlowerthanthetraditionaloneisgot.Thefixedpointoftheequationcorrespondstotheequilibriumsedimenttransportofbedload.Inthemutationanalysis,wehavefoundthattheinflectionpointisthedemarcationpointofbreaking.Intheory,thebreakingpointcorrespondstothedividingboundaryline,acrosswhichthebedformchangesfromflatbedtosandrippleorsanddune.ComparedwiththeexperimentaldataofChatouHydraulicLabinFrance,theconclusionsareverified.
简介:Effectofvelocityjumpandtemperaturejumpontheheatandmomentumtransferinmicro-domainsisdiscussedindetail.Asimulationaidedbylocallyfullydevelopedassumptionisdevelopedtoexplaintheexperimentalresultsdifferentfromthosepredictedbyconventionaltheory.Heattransferinmicro-channelsundertheuniformheatfluxisalsoanalyzed.Itisfoundthatvelocity-jumpandtemperature-jumphaveanoppositeinfluenceandNusseltnumberhasagreatervaluewhentheKnudsennumberisverysmall,WiththeincreasingofKnudsenNumber,Nussqltnumberbecamesmallerthan8.24.